The underground Shiva temple is originally known as Prasanna Virupaksha temple. It is called underground temple because it is now located few meters below the ground level. It is located near the Nobleman’s quarter after Chandikeswara temple.
We visited there in the afternoon and it was sunny day. However, the inner shrine is very dark. I took a LED torch with me on this trip to Hampi which helped me find route inside the temple and play little bit of adventurer. I spotted a baby bat hanging on the roof of the sanctum sanatorium of lord Shiva with the help of the torch otherwise it was pitch dark inside. The temple can be stylistically dated to 14th century AD. An inscription referring to this temple states that king Krishnadevaraya donated Nagalapura and other villages for worship and offering to the god for the merit of his parents Narsa Nayaka and Nagajidevi.
The temple is surrounded by a large green grass ground. We climbed down few steps to reach the large stone gate which leads to another small gate, which ultimately leads to the main temple. This part of the temple is the lowest from the ground level and always has some quantity of water and mire. The sanctum area is very dark and during monsoon you may not be able to reach there. There is small Shiva linga which probably always remains submerged.
There is no entry fee and one need not open shoes. Outside the gate we drank lime water. You can also try tender coconut water as well.